12, 18 and 30
- Whole numbers
- 12, 18, 30
- Greatest common divisor
- 6
- Least common multiple
- 180
ચકાસણીનો સ્ત્રોત: Python 3.8 math.gcd and a·b // gcd folded over the list
Greatest common divisor (GCD, GCF or HCF) and least common multiple (LCM) of two or more whole numbers, with Euclid's algorithm step by step.
અપડેટ કરેલું તપાસેલાં ઉદાહરણો: 6
The largest number dividing 12, 18 and 30 exactly is 6; the smallest positive number they all divide into is 180.
| Pair | a | b | Quotient q | Remainder r |
|---|---|---|---|---|
| gcd(12, 18) | 18 | 12 | 1 | 6 |
| gcd(12, 18) | 12 | 6 | 2 | 0 |
| gcd(6, 30) | 30 | 6 | 5 | 0 |
Divide, keep the remainder, repeat with the divisor; the last non-zero remainder is the gcd.
Divide, keep the remainder, repeat with the divisor; the last non-zero remainder is the gcd.
The greatest common divisor (GCD, also called the greatest common factor or highest common factor) is the largest whole number that divides every input; the least common multiple (LCM) is the smallest positive number that every input divides. Euclid's algorithm finds the GCD by repeatedly replacing the larger number with its remainder after division by the smaller: gcd(1071, 462) = gcd(462, 147) = gcd(147, 21) = 21. The LCM follows from lcm(a, b) = |a × b| ÷ gcd(a, b), applied a pair at a time.
Reducing fractions uses the GCD; adding fractions and lining up repeating schedules use the LCM. For the default 12, 18 and 30 the GCD is 6 and the LCM is 180, so events every 12, 18 and 30 days next coincide after 180 days.
For two numbers the calculator also gives the Bézout identity from the extended Euclidean algorithm: 21 = 1071 × (−3) + 462 × 7. Negative inputs count by their absolute value, gcd(0, n) = n, and a list containing 0 has an LCM of 0.
ચકાસણીનો સ્ત્રોત: Python 3.8 math.gcd and a·b // gcd folded over the list
ચકાસણીનો સ્ત્રોત: Wikipedia — Euclidean algorithm worked example (gcd 21); lcm and Bézout coefficients by hand back-substitution, checked in Python
ચકાસણીનો સ્ત્રોત: Wikipedia — Extended Euclidean algorithm example table (s = −9, t = 47)
ચકાસણીનો સ્ત્રોત: Both prime, so gcd 1 and lcm 17 × 31 = 527
Use Euclid's algorithm: divide the larger number by the smaller, keep the remainder, and repeat with the divisor and the remainder until the remainder is 0; the last non-zero remainder is the GCD. For 1071 and 462: 1071 = 2 × 462 + 147, 462 = 3 × 147 + 21, 147 = 7 × 21 + 0, so the GCD is 21. By Lamé's theorem it never needs more than five steps per digit of the smaller number.
Divide their product by their GCD: lcm(a, b) = a × b ÷ gcd(a, b). For 12 and 18, gcd = 6, so lcm = 216 ÷ 6 = 36. For more numbers, go one pair at a time: lcm(36, 30) = 1,080 ÷ 6 = 180, so the LCM of 12, 18 and 30 is 180. Listing multiples (12, 24, 36 …) reaches the same answer, but slowly for large numbers.
There is none: greatest common divisor (GCD), greatest common factor (GCF) and highest common factor (HCF) are three names for the same number. GCF and HCF are the usual school terms, GCF mostly in the US and HCF in the UK and India, while GCD is the name in number theory and programming, as in Python's math.gcd. Under every name, gcd(12, 18) = 6.
For two positive whole numbers, gcd(a, b) × lcm(a, b) = a × b; with 12 and 18, 6 × 36 = 216 = 12 × 18. In prime factors, the GCD takes the lower power of each shared prime and the LCM the higher power of every prime: 12 = 2² × 3 and 18 = 2 × 3², so the GCD is 2 × 3 = 6 and the LCM is 2² × 3² = 36. The product rule does not extend to three or more numbers.
Their GCD is 1, so they share no prime factor, and their LCM is simply their product. 17 and 31 are coprime, with an LCM of 17 × 31 = 527, and so are 8 and 15 although neither is prime. A fraction is in lowest terms exactly when its numerator and denominator are coprime.
ચોકસાઈ તમારા ઇનપુટ અને પદ્ધતિની ધારણાઓ પર આધારિત છે. દશાંશ ગણતરી 50 સાર્થક અંકો વાપરે છે, પરંતુ અંદાજ, સંખ્યાત્મક પદ્ધતિઓ અને મૂળ ડેટા ઓછા ચોક્કસ હોઈ શકે છે; દર્શાવેલા મૂલ્યોને રાઉન્ડ કરવાથી આ મર્યાદાઓ દૂર થતી નથી. સ્વતંત્ર સ્ત્રોતોના ઉકેલેલા ઉદાહરણો સાથે ચકાસણી: 6. ઉદાહરણ તરીકે, “12, 18 and 30”ને Python 3.8 math.gcd and a·b // gcd folded over the list સાથે ચકાસવામાં આવે છે.
Euclid, Elements, Book VII, Propositions 1–2; Knuth, The Art of Computer Programming Vol. 2, §4.5.2 (Euclid's algorithm); Wikipedia — Extended Euclidean algorithm (worked example 240, 46).
આ કેલ્ક્યુલેટરમાં સ્વતંત્ર સ્રોતોના જવાબો ધરાવતા 6 ઉકેલેલાં ઉદાહરણો છે. તે પરીક્ષણ સમૂહમાં ચાલે છે અને તમે અહીં પણ ચલાવી શકો છો.
Prime factorization of any whole number up to 60 digits, with a factor tree, a prime or composite verdict, its divisors and the nearest primes.
અપૂર્ણાંકો અને મિશ્ર સંખ્યાઓનો ચોક્કસ સરવાળો, બાદબાકી, ગુણાકાર અને ભાગાકાર કરો, તેમને લઘુતમ સ્વરૂપમાં સરળ બનાવો અને આવર્ત દશાંશ સહિત દશાંશને અપૂર્ણાંકમાં ફેરવો.
Calculate a mod n under the floored, truncated and Euclidean conventions, modular powers a^b mod m of large numbers, and modular inverses, with steps.
Factor calculator: every factor and factor pair of a whole number up to 10¹⁸, its prime factorization, divisor count and sum, and perfect or abundant.